Cooling device and method for cooling an equipment component

ABSTRACT

Described is a cooling device for cooling an equipment component with the aid of a cooling agent, as well as a method for cooling an equipment component. In at least one embodiment, the cooling device includes a heat source for transferring thermal energy from the equipment component to the cooling agent and a heat sink for dissipating thermal energy from the cooling agent. The heat source and the heat sink are connected to each other. The cooling agent can be supplied via a forward flow line to the heat source and can flow via a return line away from the heat sink. The cooling device includes a control mechanism and two storage containers or a stratified storage tank for the cooling agent. The control mechanism is connected to the two containers and/or the stratified storage tank, the forward flow line and the return flow line. The control mechanism is embodied such that in a “mixed cooling” mode, cooling agent from the two containers or the stratified storage tank is supplied at a mixing ratio to the forward flow line.

PRIORITY STATEMENT

The present application hereby claims priority under 35 U.S.C. §119 on German patent application number DE 10 2010 011 084.1 filed Mar. 12, 2010, the entire contents of which are hereby incorporated herein by reference.

FIELD

At least one embodiment of the invention generally relates to a cooling device for cooling an equipment component, and/or to a method for cooling an equipment component.

BACKGROUND

As is known, equipment components of an apparatus need to be cooled in order to maintain the proper function or to improve the function, such as the efficiency.

A device which is designed to increase the efficiency of a solar system is known from the document DE 20 2009 009 544 U1. A liquid cooling agent is used to cool a photovoltaic module. The cooling agent is collected in a central reservoir and/or in a storage container. As needed, the cooling agent is conducted while exposed past the radiation side of the photovoltaic module.

A method for cooling several heat-generating components is also known from the document DE 10 2008 003 724 A1, which method comprises a primary and a secondary cooling loop. The secondary cooling loop consists of a storage container, a pump, a heat source and a heat exchanger. The primary loop is used to cool down the cooling agent from the secondary loop. The cooling medium from the secondary loop is cooled by the primary loop during the forward flow between the storage container and the heat sources. The heat-generating components can be motors or inverters.

SUMMARY

In at least one embodiment of the present invention, the cooling of the equipment component is performed in an energy-efficient and resource-efficient manner.

With the cooling device according to at least one embodiment of the invention and the method according to at least one embodiment of the invention, it is possible to exclude the ambient temperature as a limiting factor for cooling the equipment component. The energy required for the cooling device is essentially used for operating a pump and a fan.

By using two containers for the storage, the removal and the feeding of the cooling agent, it is advantageously possible to make available cooling agent at two different temperatures in the cooling device. Cooling agent at a lower temperature can thus be removed from one of the containers, can be heated with a heating source and can then be supplied to the other container.

A control mechanism is furthermore provided which can combine cooling agents from both storage containers at a predetermined mixing ratio in a “mixed cooling” mode. With different temperatures for the cooling agents in the two containers, the control mechanism can thus make available a cooling agent mixture having a forward flow temperature between the temperatures or near the temperatures of the cooling agents from the two storage containers.

The cooling agent advantageously remains in the cooling device during the operation. In contrast to a cooling with fresh water, there is consequently no dependence of the available water resources. The water consumption of the cooling device according to the invention is furthermore essentially restricted to supplying water only once if water is used as cooling agent or as part of the cooling agent.

The use of a refrigeration unit which is distinguished by high energy consumption is advantageously omitted.

In contrast to a solution that calls for only a single storage container or a sequential arrangement of storage containers for keeping the cooling agent available, less cooling agent must on the whole be kept available, thereby resulting in lower costs for the two storage containers and also requiring less space for the two storage containers.

According to a particularly advantageous modification of the cooling device and the method, cooling agent flows in the “mixed cooling” mode from the return flow line via the control mechanism back into one of the two containers. Owing to the fact that the heated cooling agent is collected in only one storage container, the colder cooling agent can be kept ready in the other storage container.

According to another advantageous embodiment of the cooling device and the method, cooling agent is supplied in the “regeneration” mode with the aid of the control mechanism from the one container to the forward flow line. As a result, the cooling agent which is heated up in the “mixed cooling” mode can advantageously be conducted through the heat sink where it is cooled down.

According to a different advantageous embodiment of the cooling device and the method, cooling agent is supplied in the “regeneration” mode via the control mechanism from the return line to the other storage container. As a result, cooling agent which is cooled in the heat sink can advantageously be collected in only one container.

For a different advantageous embodiment of the cooling device and the method, the return line is connected in the “loop cooling” mode via the control mechanism to the forward flow line. A cooling loop is thus created which advantageously discharges heat energy from the heat source and does not use cooling agent stored in the containers.

According to yet another favorite modification of at least one embodiment of the cooling device, the control mechanism comprises a proportional valve. The proportional valve mixes the cooling agent from the one container with the cooling agent from the other container at the predetermined mixing ratio, so as to obtain the specified cooling agent mixture. The mixing of two cooling agents with different temperatures makes it possible for the resulting cooling agent mixture to have a temperature that is between the temperatures of the previously supplied cooling agents, wherein this advantageously requires only enough of the colder cooling agent to be mixed in, as is necessary to obtain a specified temperature.

According to another favorable modification of at least one embodiment of the cooling device, a fan which preferably operates with a variable speed is assigned to the heat sink. The thermal energy can thus be removed with the aid of a controlled fan operation from the cooling agent, wherein this operation can be as needed, provided the fan has a speed-controlled design.

According to one advantageous modification of at least one embodiment of the cooling device, the cooling device is assigned a pump which preferably operates at a variable speed. The pump stimulates the cooling agent to start circulating and/or moving through the cooling device, wherein this can be a demand-controlled operation when using a speed-controlled design.

One advantageous embodiment of the method provides that a measured value for the forward flow temperature of the cooling agent mixture is compared to a desired temperature value. A temperature deviation can be detected by comparing the forward flow temperature value to the desired value. On the basis of the deviation, measures can be taken to ensure that the desired value coincides with the measured forward flow temperature value.

A corresponding, advantageous modification of the method provides for generating on the basis of this comparison a signal which is then used to adjust or regulate a proportional valve to obtain the desired mixing ratio.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional features, options for use and advantages of the invention follow from the description below of example embodiments of the invention, which are shown in the Figures. All features described and illustrated therein, either by themselves or in any optional combination, represent the subject matter of the invention, regardless of how they are combined in the patent claims or their references back, as well as regardless of their formulation and/or representation in the description and/or the drawing.

The drawing shows in:

FIG. 1A cooling device for cooling an inverter;

FIG. 2 A control mechanism for the cooling device;

FIG. 3 The cooling device in a “loop cooling” mode;

FIG. 4 The cooling device in a “mixed cooling” mode;

FIG. 5 The cooling device in a “regeneration” mode;

FIG. 6 A finite automaton or state machine for the cooling device;

FIG. 7 A first control loop relating to the “loop cooling” mode;

FIG. 8 A second control loop relating to the “mixed cooling” mode; and

FIG. 9 A third control loop relating to the “regeneration” mode.

DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS

Various example embodiments will now be described more fully with reference to the accompanying drawings in which only some example embodiments are shown. Specific structural and functional details disclosed herein are merely representative for the purpose of describing example embodiments. The present invention, however, may be embodied in many alternate forms and should not be construed as limited to only the example embodiment.

Accordingly, while example embodiments of the invention are capable of various modifications and alternative forms, embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that there is no intent to limit example embodiments of the present invention to the particular forms disclosed. On the contrary, example embodiments are to cover all modifications, equivalents, and alternatives falling within the scope of the invention. Like numbers refer to like elements throughout the description of the figures.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments of the present invention. As used herein, the term “and/or,” includes any and all combinations of one or more of the associated listed items.

It will be understood that when an element is referred to as being “connected,” or “coupled,” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. In contrast, when an element is referred to as being “directly connected,” or “directly coupled,” to another element, there are no intervening elements present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between,” versus “directly between,” “adjacent,” versus “directly adjacent,” etc.).

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments of the invention. As used herein, the singular forms “a,” “an,” and “the,” are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the terms “and/or” and “at least one of” include any and all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises,” “comprising,” “includes,” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may in fact be executed substantially concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.

Spatially relative terms, such as “beneath”, “below”, “lower”, “above”, “upper”, and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, term such as “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein are interpreted accordingly.

Although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, it should be understood that these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are used only to distinguish one element, component, region, layer, or section from another region, layer, or section. Thus, a first element, component, region, layer, or section discussed below could be termed a second element, component, region, layer, or section without departing from the teachings of the present invention.

The cooling device 10 which is used to cool an inverter 22 is shown in FIG. 1. The inverter 22 is generally referred to as an equipment component. The cooling device 10 comprises a first heat exchanger 18 for cooling the inverter 22. The first heat exchanger 18, which is generally also called a heat source, is assigned to the inverter 22 and functions to remove thermal energy from the inverter 22. For that purpose, a liquid cooling agent having a lower temperature than the inverter 22 and/or the first heat exchanger 18 flows through the first heat exchanger 18 and/or flows past the first heat exchanger 18, so that thermal energy from the first heat exchanger 18 can be transferred to the cooling agent, thereby cooling the inverter 22 through the discharge of the cooling agent.

The first heat exchanger 18 is connected via a line 212 to a pump 16. The pump 16 functions to supply the first heat exchanger 18 with the cooling agent in flow direction 312. The pump 16 removes the cooling from a forward flow 208, corresponding to the flow direction 308. A forward flow temperature T_(flow) of the cooling agent in the forward flow line 208 is determined via the temperature sensor S208, which is attached to the forward flow line 208. The pump 16 is admitted with a signal C16, wherein this signal C16 functions to influence the pumping capacity of the pump. The pump 16 can be switched on or off. With a corresponding design for the pump 16, the pumping capacity of the pump 16 can be adjusted with the aid of the signal C16.

The first heat exchanger 18 is connected via a line 214 to a second heat exchanger to which a fan 24 is assigned. The second heat exchanger is generally called a heat sink. The line 214 serves to drain the cooling agent from the first heat exchanger 18 in a flow direction 314. The fan 24 functions to dissipate thermal energy from the second heat exchanger and transfer this energy to the environment. The fan 24 has a speed-controlled design. To stop the cooling action of the fan 24, the fan 24 is admitted with the signal C24. The second heat exchanger releases the cooling agent to a return flow line 216 in flow direction 316. A return-flow temperature T_(return) of the cooling agent in the return flow line 216 is detected with a sensor 5216 that is attached to the return flow line 216.

An ambient temperature T_(A) is determined with the aid of the temperature sensor SA.

The forward flow line 208 and the return flow line 216 are connected to a control mechanism 30. In flow direction 308, the forward flow line 208 represents an outlet of the control mechanism 30. In flow direction 316, the return flow line 216 represents an inlet of the control mechanism 30. The lines 202, 204, 224 and 226 are connected to the control mechanism 30. In flow direction 302, the line 202 represents an inlet of the control mechanism 30. In flow direction 304, the line 204 represents an inlet of the control mechanism 30. In flow direction 324, the line 224 functions as outlet of the control mechanism 30 and in flow direction 326, the line 226 functions as an outlet of the control mechanism 30.

The lines 202 and 226 are connected to a storage container 12. In flow direction 302, the line 202 forms an outlet for the container 12 while in flow direction 326, the line 226 serves as inlet for the tank 12. The lines 204 and 224 are connected to the tank 14. In flow direction 304, the line 204 functions as outlet for the storage container 14 while in flow direction 324, the line 224 functions as inlet for the container 14.

The containers 12 and 14 are designed to take in cooling agents via the lines 226 and/or 224, to store the cooling agents, and to subsequently dispense it via the lines 202 and/or 204.

The storage containers 12 and 14 are connected via an air supply line 232. In flow directions 334 or 336, the air supply line 232 permits an air exchange, thus also a pressure exchange, between the storage containers 12 and 14. The air supply line 232 is not used for the exchange of cooling agent between the two containers 12 and 14.

In place of the two storage containers 12 and 14, a stratified storage tank can also be used. In that case, all functions of the two containers 12, 14 are handled by the stratified storage tank. Inside the stratified storage tank, the cooling agent is layered in several regions, one above the other, wherein the temperature of the cooling agents differs in these regions. We want to point out expressly that the following description of the cooling device 10, which uses two storage containers 12, 14, applies in the same way to the use of a stratified storage tank.

The temperature T₁₂ of the cooling agent inside the container 12 is determined with a temperature sensor S12. A temperature T₁₄ of the cooling agent inside the container 14 is determined with the aid of a temperature sensor S14. Filling level sensors, which are not shown herein, are used to measure the filling level in each of the two containers 12 and 14.

FIG. 2 shows the control mechanism 30 with the lines 202, 204 and the return line 216 as inlets into the control mechanism 30, as well as the forward flow line 208 and the lines 224 and 226 as outlets from the control mechanism 30.

A proportional valve 32 is connected to the lines 202 and 204 as well as to a line 206. In flow directions 302 and 304, the lines 202 and 204 represent inlets for the proportional valve 32. In flow direction 306, the line 206 represents an outlet for the proportional valve 32. The proportional valve 32 is admitted with a signal C32.

The functionality of the proportional valve 32 comprises a first and a second control position, as well as several in-between positions. In the first control position, the proportional valve 32 connects the lines 202 and 206 and blocks the line 204, so that cooling agent flows only from the line 202 into the line 206. In the second control position, the proportional valve 32 connects the lines 204 and 206 and blocks the line 202, so that the cooling agent flows only from the line 204 into the lines 206. In an intermediate position for the proportional valve 32, the cooling agent in the line 206 is composed of cooling agent from the lines 202 and 204, corresponding to a predetermined mixing ratio, thus forming a cooling-agent mixture with the respective shares of cooling agent from both the containers 12 and 14. If there is a temperature difference between the cooling agent in line 202 and the cooling agent in line 204, it is possible on the one hand by selecting the first or second control position for the proportional valve 32 to adjust the cooling agent temperature in line 206 to match the temperature value of the cooling agent in line 202 or to adjust the value of the temperature to the cooling agent temperature value in line 204.

On the other hand, it is possible by selecting an intermediate position for the proportional valve 32, to adjust the cooling agent temperature value in line 206 to a value in-between the temperature of the cooling agent in line 202 and the temperature of the cooling agent in line 204.

A directional valve 34 is connected to the line 206, the forward flow line 208, as well as a line 218. Corresponding to the flow direction 306 and a flow direction 318, the lines 206 and 218 form inlets for the directional valve 34. In flow direction 308, the forward flow line 208 forms an outlet for the directional valve 34. The directional valve 34 is admitted with a signal C34.

The functionality of the directional valve 34 comprises a first and a second control position. The first control position connects the line 218 and the forward flow line 208 and blocks the line 206, so that cooling agent flows from the line 218 into the forward flow line 208. The second control position connects the line 206 and the forward flow line 208 and blocks the line 218, so that cooling agent flows from the line 206 into the forward flow line 208. No intermediate positions are provided.

A directional valve 36 is connected to the return line 216 and the line 218 as well as to a line 222. In flow direction 316, the return line 216 functions as inlet for the directional valve 36. In flow direction 318 and in a flow direction 322, the lines 218 and 222 form outlets for the directional valve 36. The directional valve 36 is admitted with a signal C36.

The functionality of the directional valve 36 comprises a first and a second control position. In the first control position, the return line 216 and the line 218 are connected and the line 222 is blocked, so that cooling agent flows from the return line 216 into the line 218. In the second control position, the return line 216 and the line 222 are connected and the line 218 is blocked, so that cooling agent flows from the return line 216 into the line 222. No intermediate positions are provided.

A directional valve 38 is connected to the lines 222, 224 and 226. In flow direction 322, the line 222 forms an inlet of the directional valve 38. In flow directions 324 and 326, the lines 224 and 226 form outlets for the directional valve 38. The directional valve 38 is admitted with a signal C38.

The functionality of the directional valve 38 comprises a first and a second control position. In the first control position, the lines 222 and 224 are connected and the line 226 is blocked, so that cooling agent flows from the line 222 into the line 224. In the second control position, the lines 222 and 226 are connected and the line 224 is blocked, so that cooling agent flows from the line 222 into the line 226. No intermediate positions are provided.

In a “loop cooling” mode for the cooling device 10, the directional valves 34 and 36 of the control mechanism 30 are in a respective control position where the lines 206 and 222 are blocked and the return line 216 is connected to the forward flow line 208. The control mechanism 30 is thus in a state where the cooling agent flows from the return line 216 into the forward flow 208.

In a “mixed cooling” mode of the cooling device 10, the directional valves 34, 36 and 38, as well as the proportional valve 32, of the control mechanism 30 are in the respective control and/or intermediate position, so that the line 226 is blocked, the return line 216 is connected to the line 224 and the line 202 as well as the line 204 are connected to the forward flow line 208. The control mechanism 30 is thus in a state in which the cooling agent flows from the return line 216 into the line 224 and cooling agent from one of the lines 202 and/or 204, or cooling agent from the two lines 202 and 204 at the specified mixing ratio, flows into the forward flow line 208.

In the “regeneration” mode of the cooling device 10, the directional valves 34, 36, 38, as well as the proportional valve 32 of the control mechanism 30, are in a respective control and/or intermediate position, so that the lines 202 and 224 are blocked, the line 204 is connected to the forward feed line 208, and the return line 216 is connected to the line 226. The control mechanism 30 is thus in a state in which the cooling agent from the line 204 flows into the forward flow line 208 and the cooling agent from the return line 216 flows into the line 226.

A cooling agent composed of a glycol/water mixture is used owing to a high heating capacity. The glycol/water mixture is composed, for example, of 20% glycol and up to 80% water.

FIG. 3 shows the cooling device 10 in the “loop cooling” mode. Corresponding to the marking 40, the cooling agent flows in a cooling loop. The pump 16 pumps the cooling agent from the forward flow line 208 into the line 212 that leads to the first heat exchanger 18. In the first heat exchanger 18, the cooling agent absorbs thermal energy and, after flowing through the line 214, releases the thermal energy with the aid of the second heat exchanger and the fan 24. From the fan 24, the cooling agent then travels via the return flow line 216 to the control mechanism 30. In the “loop cooling” mode, the control mechanism 30 conducts the cooling agent from the return line 216 via the line 218 in flow direction 318 to the forward flow line 208. The cooling agent in the containers 12 and 14 is not used in the “loop cooling” mode.

The “loop cooling” mode is activated, for example, during a normal ambient temperature T_(A) below 40° C. At normal ambient temperatures T_(A) the cooling with the fan 24 is sufficient to achieve a first desired value for the forward flow temperature T_(flow) of 43° C. which is necessary for cooling the inverter 22. It means that a normal cooling capacity demand exists for cooling the inverter 22.

If the inverter 22 of a photovoltaic system is cooled, for example, then the “loop cooling” mode is preferably activated during the first half of the day in which radiation from the sun is present but the ambient temperature T_(A) is still low enough to cool the inverter 22.

FIG. 4 shows the cooling device 10 in the “mixed cooling” mode. The cooling agent flows through the cooling device 10 as shown with the marking 50. The cooling agent from the containers 12 and 14 is supplied via the lines 202 and 204 to the control mechanism 30. In the control mechanism 30, the cooling agent from the line 202 and the cooling agent from the line 204 are combined at a junction 338. The junction 338 corresponds to the proportional valve 32 shown in FIG. 2. The cooling agent with the temperature T₁₂ from the container 12 and the cooling agent with the temperature T₁₄ from the container 14 are mixed at a predetermined mixing ratio at the junction 338 to form a cooling-agent mixture. Once the cooling agent has flown through the line 206, the forward flow temperature T_(flow) is determined in the forward flow line 208. The pump 16 pumps the cooling agent from the forward flow line 208 into the line 212 and to the first heat exchanger 18. The first heat exchanger 18 transfers thermal energy to the cooling agent and conducts the cooling agent via the line 214 to the fan 24. The fan 24 then extracts thermal energy from the cooling agent and conducts the cooling agent via the return line 216 to the control mechanism 30. The control mechanism 30 connects the return line 216 via the line 222 to the line 224 and thus supplies the cooling agent to the container 14.

In the “mixed cooling” mode, the cooling agents from the containers 12 and 14, having the respective temperatures T₁₂ and T₁₄, are mixed at the predetermined mixing ratio inside the control mechanism 30, so as to result in a second desired value for the forward flow temperature T_(flow) of 43° C. Before entering the “mixed cooling” mode, the container 14 ideally should contain very little cooling agent whereas the container 12 should hold the major share of the existing cooling agent. The temperature T₁₂ of the cooling agent in the container 12 is furthermore lower than the second desired value for the forward flow temperature T_(flow).

The “mixed cooling” mode is normally used if the cooling down with the aid of the fan 24, for example taking place in the “loop cooling” mode, is no longer sufficient to reach the first desired value for the forward flow temperature T_(flow). It means that with a high ambient temperature T_(A) above 40° C., for example, there is a high cooling capacity demand for cooling the inverter 22.

In the “mixed cooling,” mode, the return temperature T_(return) is normally higher than the forward flow temperature T_(flow), despite the dissipation of thermal energy by the fan 24. To prevent air from entering the lines of the cooling device 10, the two containers 12 and 14 are normally operated in such a way that they are never completely empty.

If the two containers 12 and 14 hold sufficient cooling agent for pumping, then the proportional valve 32 from FIG. 2, which is located at the junction point 338, is adjusted such that the forward flow temperature T_(flow) of cooling agent in the forward flow line 208 corresponds to the second desired value for the forward flow temperature T_(flow).

The “mixed cooling” mode can be continued until the second desired value for the forward flow temperature T_(flow) can be maintained and/or as long as cooling agent with the required temperature T₁₂ and T₁₄ is present in the storage container 12.

The “mixed cooling” mode results in an additional feature for the two containers 12 and 14, wherein both containers 12 and 14 must respectively hold the same volume. If one of the containers 12 or 14 is empty, then the other container 14 or 12 must hold the total cooling agent volume, excluding the amounts still in the lines and/or other parts of the cooling device 10.

As soon as the fan 24 in the “loop cooling” mode is not longer capable of sufficiently cooling down the cooling agent to ensure the required cooling of the inverter 22, for example if the ambient temperature T_(A) is above 40° C., the “mixed cooling” mode is activated. A high demand for cooling can occur in particular during the afternoon hours. The cooling agent mixture made available in that case contains only enough of the required colder cooling agent as is necessary to reach the second desired value for the forward flow temperature T_(flow).

With a photovoltaic system, for example, the “mixed cooling” mode is activated especially during the second half of the day. A correspondingly cooled cooling agent and/or a cooling agent mixture is to be made available in particular at locations where the ambient temperature T_(A) is at times higher than the required forward flow temperature T_(flow).

FIG. 5 shows the cooling device 10 in a “regeneration” state. The cooling agent is conducted through the cooling device 10 as shown with the marking 60. For this, the control mechanism 30 is in a state where the cooling agent from the container 14 is conducted via the line 204 and the line 206, shown in FIG. 2, to the forward flow line 208. Cooling agent is furthermore conducted from the return line 216 via the line 222, shown in FIG. 2, to the line 226. The “regeneration” mode is used to pump cooling agent with the temperature T₁₄ from the container 14 through the cooling device 10, in such a way that cooling agent with the temperature T₁₂, which is lower than the temperature T₁₄, is collected in the container 12. Ideally, the temperature T₁₂ should be identical to the ambient temperature. T_(A).

The inverter 22 and thus also the first heat exchanger 18 are generally not operational in that case. The cooling agent flowing through the first heat exchanger 18 is therefore essentially not heated up. The fan 24 is used for cooling down the cooling agent, corresponding to a desired value to be achieved for the return-flow temperature T_(return). The selection of the desired value for the return-flow temperature T_(return) depends on the location and is selected in dependence on the standard nighttime temperatures at the different locations. In Spain, for example, a temperature range of 20° C. to 25° C. can be specified for the desired value of the return-flow temperature T_(return), wherein a higher temperature range of 30° C. to 35° C. may be required for the desired value of the return-flow temperature T_(return) in Dubai.

The “regeneration” mode remains activated until the total volume of cooling agent that can be pumped from the container 14 has been transferred to the container 12 and/or until the cooling agent can be cooled down. A cooling down of the cooling agent is possible, for example, only as long as the ambient temperature T_(A) remains below a specified value.

A photovoltaic system, for example, is normally not operated during the night because there is no irradiation from the sun. That is the reason why the cooling agent in the cooling device 10 is not heated up by the inverter 22 and/or the first heat exchanger 18. As a result, the cooling agent which is heated up during the day in the “mixed cooling” mode can be conducted during the night through the cooling device 10. In the process, the cooling agent is cooled down by the fan 24, ideally to the ambient temperature T_(A), and is collected in the container 12. The ambient temperature T_(A) is 25° C. for example. The cooling agent is then available in the container 12 for the next time the “mixed cooling” mode is required.

FIG. 6 shows a finite automaton or state machine 70, used for operating the cooling device 10. This finite automaton 70 comprises a starting state 72, a state 74 that corresponds to the “loop cooling” mode for the cooling device 10 shown in FIG. 3, a state 76 that corresponds to the “mixed cooling” mode for the device 10 shown in FIG. 4, and a state 78 that corresponds to the “regeneration” mode for the cooling device 10 shown in FIG. 5. A no-load state, meaning a state where the cooling agent does not circulate, for the cooling device 10 is not shown herein.

A transition 72-74 transitions the finite automaton from the starting state 72 to the state 74. This transition 72-74 is implemented following the start-up of the finite automaton 70.

By implementing a transition 74-76, the finite automaton 70 is transitioned from the state 74 to the state 76. The transition 74-76 is implemented once the ambient temperature T_(A) in FIG. 1 exceeds a temperature value of 40° C., for example, and while the inverter 22 is operational, thus resulting in a switch from the “loop cooling” mode to the “mixed cooling” mode.

By implementing a transition 76-74, the finite automaton 70 is transitioned from the state 76 to the state 74. The transition 76-74 is carried out, for example, once the ambient temperature T_(A) in FIG. 1 drops below a value of 40° C. and while the inverter 22 is operational, thus switching from the “mixed cooling” mode to the “loop cooling” mode.

By implementing a transition 76-78, the finite automaton 70 is transitioned from the state 76 to the state 78. The transition 76-78 takes place, for example, if the ambient temperature T_(A) drops below a value of 25° C. and the inverter 22 is not operational. The “mixed cooling” mode is thus switched to the “regeneration” mode.

By implementing a transition 74-78, the finite automaton 70 is transitioned from the state 74 to the state 78. The transition 74-78 takes place, for example, if the ambient temperature T_(A) drops below a value of 25° C. and the inverter 22 is not operational. The “loop cooling” mode is thus switched to the “regeneration” mode.

By implementing a transition 78-74, the finite automaton 70 is transitioned from the state 78 to the state 74. The transition 78-74 takes place while the inverter 22 is operational. The “regeneration” mode is thus switched to the “loop cooling” mode.

FIG. 7 shows a first control loop 80 for the “loop cooling” mode. The forward flow temperature T_(flow) functions as control variable for the first control loop 80. The forward flow temperature T_(flow) is determined with the aid of a controlled system 84, is supplied via the feedback 86 to a location 87, and is subtracted from the first desired value T_(flow,SP1) of the forward flow temperature T_(flow). The subtraction at the location 87 results in a control deviation 88 which is supplied to a controller 82. The controller 82 determines the signals C16 and C24 which are supplied as adjustment variables to the controlled system 84. The signal C16 influences the pumping capacity of the pump 16 and thus a flow speed for the cooling agent. The signal C24 influences the speed of the fan 24 and thus the dissipation of thermal energy from the cooling agent. The controller 82 is embodied to influence the signals C16 and C24 in such a way that the determined forward flow temperature T_(flow) as control variable over time tends toward the first desired value T_(flow,SP1) of the forward flow temperature T_(flow).

FIG. 8 shows a second control loop 90 for the “mixed cooling” mode. The forward flow temperature T_(flow) serves as the control variable for the second control loop 90. The forward flow temperature T_(flow) is determined with the aid of a controlled system 94, is supplied via the feedback 96 to a location 97 and is subtracted from the second desired value T_(flow,SP2) of the forward flow temperature T_(flow). The subtraction at the location 97 results in a control deviation value 98 which is then supplied to a controller 92. The controller 92 determines the signals. C16, C24 and C32 which are supplied as adjustment variables to the controlled system 94. The signal C16 influences the pumping capacity of the pump 16 and thus the flow speed of the cooling agent. The signal C24 influences the rotational speed of the fan 24 and thus the dissipation of thermal energy from the cooling agent. The signal C32 influences the position of the proportional valve 32 and thus the composition of the cooling agent mixture from the two containers 12 and 14. The controller 92 is embodied to influence the signals C16, C24 and C32 in such a way that the determined forward flow temperature T_(flow) as control variable over time tends toward the second desired value T_(flow,SP2) of the forward flow temperature T_(flow).

FIG. 9 shows a third control loop 100 for the “regeneration” mode. The return-flow temperature T_(return) functions as the control variable for the third control loop 100. The return-flow temperature T_(return) is determined with the aid of a controlled system 104, is supplied via the feedback 106 to a location 107 and is subtracted from the desired value T_(return,SP) of the return-flow temperature T_(return). The subtraction at the location 107 results in a control deviation 108 which is supplied to a controller 102. The controller 102 determines the signals C16 and C24 which are supplied as adjustment variables to the controlled system 104. The signal C16 influences the pumping capacity of the pump 16 and thus the cooling agent flow speed. The signal C24 influences the speed of the fan 24 and thus the dissipation of thermal energy from the cooling agent. The controller 102 is embodied to influence the signals C16 and C24 in such a way that the determined return-flow temperature T_(return) as control variable over time tends toward the desired value T_(return,SP) of the return-flow temperature T_(return).

The cooling device 10 and the method for cooling an equipment component can also be used for systems and equipment components other than the ones described in the above. The cooling device 10 is suitable for use, in particular with equipment components which have a high demand for cooling capacity and which provide the option for a return cooling and/or regeneration of the cooling agent.

The patent claims filed with the application are formulation proposals without prejudice for obtaining more extensive patent protection. The applicant reserves the right to claim even further combinations of features previously disclosed only in the description and/or drawings.

The example embodiment or each example embodiment should not be understood as a restriction of the invention. Rather, numerous variations and modifications are possible in the context of the present disclosure, in particular those variants and combinations which can be inferred by the person skilled in the art with regard to achieving the object for example by combination or modification of individual features or elements or method steps that are described in connection with the general or specific part of the description and are contained in the claims and/or the drawings, and, by way of combinable features, lead to a new subject matter or to new method steps or sequences of method steps, including insofar as they concern production, testing and operating methods.

References back that are used in dependent claims indicate the further embodiment of the subject matter of the main claim by way of the features of the respective dependent claim; they should not be understood as dispensing with obtaining independent protection of the subject matter for the combinations of features in the referred-back dependent claims. Furthermore, with regard to interpreting the claims, where a feature is concretized in more specific detail in a subordinate claim, it should be assumed that such a restriction is not present in the respective preceding claims.

Since the subject matter of the dependent claims in relation to the prior art on the priority date may form separate and independent inventions, the applicant reserves the right to make them the subject matter of independent claims or divisional declarations. They may furthermore also contain independent inventions which have a configuration that is independent of the subject matters of the preceding dependent claims.

Further, elements and/or features of different example embodiments may be combined with each other and/or substituted for each other within the scope of this disclosure and appended claims.

Example embodiments being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. 

1. A cooling device for cooling an equipment component with the aid of a cooling agent, said cooling device comprising: a heat source to transfer thermal energy from the equipment component to the cooling agent; a heat sink to dissipate thermal energy from the cooling agent, the heat source and the heat sink being connected, the cooling agent being suppliable to the heat source via a forward flow line and being drainable via a return-flow line from the heat sink; at least two storage containers or alternatively a stratified layer tank to hold the cooling agent; and a control mechanism connected to the at least two storage containers or to the stratified layer tank, the forward flow line and the return-flow line and the control mechanism being embodied such that in a “mixed cooling” mode, the cooling agent from the at least two storage containers or from the stratified layer tank is suppliable at a mixing ratio to the forward flow line.
 2. The cooling device according to claim 1, wherein the control mechanism is embodied such that in the “mixed cooling” mode, the cooling agent is able to flow from the return-flow line into at least one of the at least two storage containers or into the stratified layer tank.
 3. The cooling device according to claim 1, wherein the control mechanism is embodied such that in a “regeneration” mode, the cooling agent is suppliable from the at least two storage containers or from the stratified layer tank, to the forward flow line.
 4. The cooling device according to claim 3, wherein the control mechanism is embodied such that in the “regeneration” mode, the cooling agent is suppliable from the return-flow line to at least one other of the at least two storage containers or to the stratified layer tank.
 5. The cooling device according to claim 1, wherein the control mechanism is embodied such that in a “loop cooling” mode, the return-flow line is connected to the forward flow line.
 6. The cooling device according to claim 1, wherein the control mechanism comprises a proportional valve, which is embodied such that cooling agent, from the at least two storage containers or from the stratified layer tank, is mixed together at the mixing ratio.
 7. The cooling device according to claim 1, wherein a temperature sensor is provided to measure a forward flow temperature of the cooling agent in the forward flow line.
 8. The cooling device according to claim 1, wherein a temperature sensor is provided to measure a return-flow temperature of the cooling agent in the return flow line.
 9. The cooling device according to claim 1, wherein the equipment component is an inverter.
 10. The cooling device according to claim 1, wherein a fan is assigned to the heat sink.
 11. The cooling device according to claim 1, wherein the cooling device comprises a pump.
 12. A method for cooling an equipment component with the aid of a cooling agent and a cooling device, the cooling device including a heat source for transferring thermal energy from the equipment component to the cooling agent, and a heat sink for dissipating thermal energy from the cooling agent, the heat source and the heat sink being connected to each other, the cooling agent being suppliable via a forward flow line to the heat source and being drainable via a return flow line from the heat sink, and the cooling device including at least two storage containers or alternatively a stratified storage tank for the cooling agent, and including a control mechanism connected to the at least two storage containers or to the stratified storage tank, the forward flow line and the return flow line, the method comprising: supplying, in a “mixed cooling” mode, the cooling agent with the aid of the control mechanism from the at least two containers or from the stratified storage tank, at a mixing ratio, to the forward flow line.
 13. The method according to claim 12, wherein in the “mixed cooling” mode, the cooling agent flows from the return flow line through the control mechanism into at least one of the two containers or into the stratified storage tank.
 14. The method according to claim 12, wherein in a “regeneration” mode, the cooling agent, from at least one of the two containers or from the stratified storage tank, is supplied via the control mechanism to the forward flow line.
 15. The method according to claim 14, wherein in the in the “regeneration” mode, the cooling agent flows from the return flow line via the control mechanism to at least one other of the at least two containers or to the stratified storage tank.
 16. The method according to claim 12, wherein in a “loop cooling” mode, the return flow line is connected via the control mechanism to the forward flow line.
 17. The method according to claim 12, wherein for determining the mixing ratio, a measured forward flow temperature of the cooling agent is compared to a desired value.
 18. The method according to claim 17, wherein on the basis of this comparison, a signal is generated for adjusting or controlling a proportional valve of the control mechanism, so as to obtain the desired mixing ratio.
 19. The cooling device according to claim 10, wherein the fan operates with a variable speed.
 20. The cooling device according to claim 11, wherein the pump includes a changeable speed.
 21. The method according to claim 13, wherein in a “regeneration” mode, the cooling agent, from at least one of the two containers or from the stratified storage tank, is supplied via the control mechanism to the forward flow line.
 22. The method according to claim 21, wherein in the in the “regeneration” mode, the cooling agent flows from the return flow line via the control mechanism to at least one other of the at least one two containers or to the stratified storage tank. 